[doc] Fix badge URL

Author: lpinca

README.md

@@ -1,7 +1,7 @@
 # bufferutil
 
 [![Version npm](https://img.shields.io/npm/v/bufferutil.svg?logo=npm)](https://www.npmjs.com/package/bufferutil)
-[![Linux/macOS/Windows Build](https://img.shields.io/github/workflow/status/websockets/bufferutil/CI/master?label=build&logo=github)](https://github.com/websockets/bufferutil/actions?query=workflow%3ACI+branch%3Amaster)
+[![Linux/macOS/Windows Build](https://img.shields.io/github/actions/workflow/status/websockets/bufferutil/ci.yml?branch=master&label=build&logo=github)](https://github.com/websockets/bufferutil/actions?query=workflow%3ACI+branch%3Amaster)
 
 `bufferutil` is what makes `ws` fast. It provides some utilities to efficiently
 perform some operations such as masking and unmasking the data payload of